Automatic chain or belt tightener



- July 28, 1931. J o 1,815,954

AUTOMATIC CHAIN OR BELT TIGHTENER Filed Feb. 27, 1928 2 Sheets-Sheet l INVENTOR 77 7460 164,, 0 1:-

ATTORNEYS Patented July '28:

'rzia vnsr Jot-IN orriaor' MENArIns, NEW YORK, ASSIGNOR 'ro RAMSEY AINCQ, r ve; f

or nnnnniyivnw YORK, A CORPORATION or New ,YonK

oHAI'ri on BELT TIGHTENER Application fi 'eqreb 'r 27, 192s; Serial No. 257,349. 1

1 invent-ion i-"elate's to belt or chain in of belts or chainsused for driving mechis made for adjustmentand attempts have been made to provide for taking up the slack "automatically. "Some devices: intended to\ accomplish this objectaare' available but they -are generally 'unadaptedfor installation in machines wherev compactness and: simplicity are essential. j p I It is the object of the present invention to provide a simple, compact-and elfective'de- =vice which will automatically take ,up the slack of a belt" or chain and maintain auniform andpredetermined tension thereof.

@In carrying out the invention I provide a framewhieh is adapted to be mounted on any-suitablefixed support-and carries a'slid-' able hub on which a pulley or gear is rotatably mounted. The pulley'or gear is adapted to be engaged by the belt or chain. The

hub isslotted toireceive a block having an angularface which'cooperates with a similar face on the hub/The block acts as a wedge under the influence of a springto move the hub against the tension of the belt or chain.

V When the belt orflchain is adjusted the hub is disposed in neutral position, that is to say, it f is centered -in the. frame. As the,

. belt or chain jelongates in service the an I sionof thespringacting through the wedge moves'the hub in the frame from its neu 'tral position until the limit'of such move- I ment isreachedi The range, of movement of the hub maybe sufficient to take up the slack which develops inithe' belt or chain .-during the normal life thereof so that the 1 4 belt or chain is always I maintained under a? suitable tensionto ensure maximum eflicien'cy. y i a The'invention maybe embodied in various forms. Thus a singlewedging block or two opposed blocks cooperating with'suitable angular faces on the hub may be used. one-or more springs may be provided'to secure the desired or necessary tension. The spring or springs maybe arranged so that adjustment of the tension may be made to meet the conditions of most eificientoperation. Anysuitable pulley or sprocket may be provided to cooperate with the belt or chain.v Thus, if a pulley is used it may bea straight faced or V-type pulley and if'a sprocket is employed it maybe adapted for .silent or ordinary rollerchain. v 3

Two forms ofthe'inventionare shown as examples of suitable structures in the accompanyingdrawings, in which I Fig. 1 "s a sectional view of the device showing the hub in neutral'position;

, Fig. 2 isasimilar view with thehub dis-1 I posed at the limitofits movement;

' Fig. 3 is a section on the line 33 of Fig.- 2;

Fig. 4. isa section on the line 4'-4 of Fig. 1;

Fig. 5 is'a section on the line 55.of Fig. 2 ;and 1. Figs. 6 and 7 are sectional views of a modified form of the device embodying two wedging' blocks.

Referring to cate the oppositely disposed members ofthe frame which are connected by bolts 7. The

member :5 has a laterally projecting shank 8 which 'isadapted to be mounted. in any. suitable stationary support. The members5 and 6 of the' frame are" provided withinwardly projecting ribs 9and 10 which are engaged in corresponding grooves formed in a hub 11 so that the hub is slidable in a straight line relatively totheframe; The

'hubjforms a bearing for a rotatable member such as a sprocket 12, the latter being provided preferably with a bushing 13 to re- .75 the drawings, 5 and 6 indiduce the friction incident-to the rotation of the sprocket'on the hub. The hub 11 is provided with slots 14 embracing the bolts 7; I

we. Y i

hub and resiliently tensioned wedging means the hub in positionto take up slack in the 'revolves,,said sliding hubv having an elon- 10. The combination for sliding the hub in the frame. In an automatic device for tightening belts and chains, the combination of a frame having inwardly projecting ribs, a hub hav-" ing'grooves cooperating with the ribs to per- 'mit sliding movement 1 of the hub inthe frame, a rotatable member mounted ,on'the hub, resiliently tensioned wedging means for sliding the hub in the frame and means for adjusting the tension of the last-mentioned means. Y

7. The combination in an automatic takeup device of a sprocket wheel'over which a chain passes, a slotted sliding hub on which the sprocket wheel revolves, a sliding wedge locatedin the elongated slot of the sliding hub with its angular face fitting against the angular side of saidelongated slot.

up device of a sprocket overwhich a chain for adjusting the tension of the last-mentioned means.

14. In an automatic device for tightening belts andchains, the combination of a frame, a member slidable therein and providing a bearing, a rotatable member mounted thereon, the member having a slot with a face 'angularly disposed with respect to the axis of the member, a wedge in the slot having. a cooperating faceand resilient means engaging the wedge to slide the member in the frame.

15. In an automatic device for tightening belts and chains, the combination of a frame having inwardly projecting ribs, a member having grooves cooperating with the ribs to permit sliding movement of the member in the frame, a rotatable member mounted on the member and resiliently tensioned wedging means for sliding the member in the frame. p c In testimony 8. The combination in an automatic takewhereof I aflix my signature.

ERNEST JOHN OPIE.

passes, a sliding hub on'which the sprocket revolves, a taper wedge fitted into the sliding hub, a coil spring arranged to yieldingly move chain, and a screw plug against the spring for adjusting the tension of the coil spring.

9. The combination in an automatic takeup device of a sprocket over whichja chain passes, a sliding hub on which the sprocket gated recess in samepo'ne end'of which has a double angular side in relation to the center line of the hub.

inanautomatic takeup device of a sprocket over which alchain 1 passes, a sliding hub with an elongated re-* cess in same, with one end of said recess having a double angular arrangement with the centre line'of the hub and two sliding wedges,

each. one fittedto'onerofthe angles of the elongated recess so as to be oppositefrom each'other. g 11. The combination in an automatic take up device of a sprocket over which a chain yieldingly hold thehub in position so that when slack occurs in the drive chain it' will beautomatically takenup.by the spring.

12. In an automatic device for tightening belts and chains,the combination of a frame, a member slidabletherein and providing a bearing,a rotatable member mounted thereon and resiliently tensioned wedging means for sliding the member in the frame. I

13. In an automatic device, for tightening v belts and chains,the'combination of a frame,

a member slidahle. therein andproviding a bearing, a rotatable member mounted thereon, resiliently-tensioned wedging means for sliding the member inthe frame and means 

